Percussive tool for scaling tubes.



H. S. B. BRINDLEY.

PERcussxvE Tom FOR scALlNe TUBES.

APPLICATION FILED MAY 23| 19I4. 1,1 ,l 15, Patented 061;. '26, 1915.

A rr'y PERCUSSIVE TOOL FOR SCALING TUBES.

Specification of Letters Patent.

Patented Oct. 26, 1915.

Application filed May 28, 1914. Serial No. 841,428.

To all whom it may concern.'

Be it known that I, HARRY SAMUEL Bioniin'ron BnrNnLnY, a subject of l-lis Majesty the ling ot Great Britain and ireland, residing at 57 Overstrand Mansions, Battersea Park, London, England, consulting engineer, have invented new anduseful improvements in Percussive Tools for Scaling Tubes, of which the following is afspecitlcation. l

rlhis invention has vreference to percussive tools for removing scale from the interior ot all kinds ot tubes and particularly those of water tube boilers. v

The type of scaling tool to which this invention relates comprises a pneumatic or other fluid pressure hammer furnished at its fore part with a series oi' cutters which are driven forwardly and outwardly against the scale by the rapid blows of the hammer piston. y

According to this invention the cutters are mounted in the fore end ot, and are carried by, a cylindrical sleeve which is adapted to slide on the hammer cylinder containing the hammer piston by which the cutters are struck, the acting ends of the cutters projecting in front of the sleeve and a cushion being arranged between the sleeve and the cylinder and hammer piston so as to maintain the cutters in operative position within range of the hammer piston, the cushion serving to partly absorb the shocks on the cutters when struck by the hammer piston and the fore ends of the cutters are not in contact, or only partly in Contact, with the scale. Thus the breaking oi the cutters by the repeated blows on their' back ends when their fore ends are not striking the scale is reduced to a minimum. y e

The cutters are maintained in engagement with the mouth of the sleeve by means ot a central supporting member fixed to the hammer cylinder and on which the hammer slides and which also serves as a duct to lead the fluid under pressure into vthe cylinder.

This invention is illustrated by the accompanying drawings of which Figure 1 is a sectional. elevation of a percussive tubescaling tool constructed in accordance with this invention; Fig. 2 is a longitudinal sectional elevation of the sleeve and cutters separately; Fig. 3 is a cross sec# tional elevation ot the sleeve and cutters taken on line X X of Fig. 2.

ln the preferred arrangement of carrying this invention into eifect the cutters'l of which there may be 'any convenient number, say siX, as shown, are mounted in the fore end of a cylindrical sleeve 2 which tits and slides on the outside of the hammer cylinder 3 which contains the'hammer piston Li, the i'ore end 5 of which is slightly coned inwardly and is adapted to strike the back ends G of the cutters 1. The acting ends 7 of the cutters project in front ot the sleeve 2 and the cutters 1 engage with the sleeve preterably by each cutter having an arc shaped rounded rib 8 which engages in an annular groove 9 in the interior ot the sleeve 2 and the cutters are retained in engagement with the sleeve by a central lcircular stem like member 10 which passes through and is fixed to the back end 11 of the cylinder 3, this stem also passing through the piston i and through the end of the cylinder' and being bored with an axial hole 12-to serve as an 1nlet for the compressed air or other fluid under pressure for operating the hammer l. The inner surfaces 13 of the cutters 1 are rounded so as to slide on the part 10 when the cutters rock in theannular groove 9 of the sleeve. The back ends 6 of the cutters are inclined at 111 and are adapted to be engaged on each'forward stroke by the coned tore end 5 of the reciproca-ting hammer 4f whereby the inner ends 6 oi" the cutters are forced together as indicated by the dotted lines in Fig. 2 thereby swinging the outer ends 7 outwardly and at the same time driving the cutters 1 on the sleeve 8 forward to some extent so that the movement of the cutters on the scale is avcombined longitudinal andoutward radial movement. The stem 10 is fixed to the cylinderv 8 by the back part of the stem 10 being screw threaded .and screwed into a bush 11 forming a portion of' the back of the cylinder and fitting therein with two lock nuts 15- screwed on to the stem 10 locking the same air-tight in the back of the cylinder. rlhe tore part 5 of t-he hammer piston tits and slides in the fore part of the cylinder 3 which is made ot' slightly larger diameterthan the rear portion 16 of the cylinder into which the back part of the hammer piston extends, but does not lit. This back part of the hammer piston lits and slides at 17 on the part 18 of the stem 10 and this latter is made with an enlarged collar 19 on which the interior of the hammer piston l lits and slides, y the terminations 20, 21 of this collar part 10 serving `with the side ports 22 in the. ham- `mer piston to control the an' admission to the cylinder 3 and the exhaust therefrom.

In operation, the compressed air or other fluid enters the back end of the stem l at the'inlet l2 and flowing through two side ports 22 therein enters the space 23 in the hammer piston and maintains a constant pressure therein to effect the back stroke of the hammer piston andwhen the part 4 has passed the edge of the swell l0 the live air passes from the space through the ports 22 ofl the piston into the cylinder 3 so as to -act on the piston -land drive it forward until it has moved so far forward that the ports 92 are opened ley passing tlie edge 2l, nliieli permits tle an' te exhaust inte [the fore part of tlie cylinder, llllien tlie ei;- haust takes place as aforesaid some exhaust passages in the fore part of the cylinder are opened by the forepart of the piston passing them so that some of the exhaust air then flows into the annular space 25 bey tween the sleeve and the cylinder and so on back to an internal annular recess 2G which is formed within the 'sleeve and around the outside 'of the cylinder, so as to `form an any nular air cushion into which the exhaust air flows from the annular space 25 through small flat spaces or passages 27 in the shoulder'QEon the cylinder at the commencement y ofthe annular chamber 26 and which would bev closed by the rsleeve when the latter is movedforward for a certain distance thereby iniprisonimg; the exhaust air in the eX- haust chamber 26 and forming a cushion so that `the expansion of the air in this chamber 26 will tend tov draw the sleeve and cutters l backwardly `nearer to the cylinder and hammer piston, and the cushion will partly vabsorb the shocks on the cutters when struck by the hammer piston and the fore ends of the cutters are not in contact or are only partly in Acontact withthe scale, thus preventing or minimizing the breaking of the cutters by the repeated blows as aforesaid.

yIf, desired a coiled spring such as 31 may be employed in the cushion chamber so as to assist the air cushion therein as aforesaid. This spring` can coiivenicntly be arranged to act between the shoulder 28' on the cylinder and the internal vcolla-r or shoulder 29 on the sleeve whichfits and slides on the `smaller back portion of the cylinder. The cup part 30 which is screwed and locked on tothe back end of the stem l0 fits inside the back end lof the sleeve 2 and serves to prevent dirt getting on to the back of the cylinder and `also serves as a stop to limit the backward movement of the sleeve 2.

W hat claim as my'invention and desire to secure by Letters Patentisi-r n 1. In a percussive tube scaling tool operated by pneumatic or other fluid pressure, a sleeve, a series of cutters provided at the fore end of the sleeve and having forward and outward motion, a reciprocating haininer piston controlling the motion of said cutters, a cylinder, a central pressure admitting member to which said cylinder is fixed, said sleeve boingk slidably mounted on the cylinder and meansV for returning and cusl1- inning the sleeve and cutters after cach forward stroke, substantially as set forth.

2. In a percussire tube scaling tool operated by pneumatic or other fluid pressure, a sleeve, a series of cutters at the forward end of the sleeve and mounted for forward and outward motion, a reciprocating lianinier piston operating said sleeve and cutters, a cylinder, a central pressure l dnnttinp ineinlier petitioned between fnnl sleeve :nal lnnn i n nier and te wlnci said cylinder is nxed, the sleeve being slidably mounted on the cylinder and means between the sleeve and cylinder to form a cushion for the sleeve and cutters,

3. ln a percussive tube scaling tool operated by pneumatic or other fluid pressure, a sleeve, a series of cutters at the forward end of the sleeve and mounted for forward and outward motion, a reciprocating hammer piston operating said sleeve and cutters, a cylinder, and a central pressure admitting member positioned between said sleeve and hammer and to which said cylinder is fixed, said sleeve being slidably mounted on the cylinder, there being an annular recess between said sleeve and cylinder communicating with the central pressure admitting member, substantially as set forth.

4. A perciissive tube scaling tool operated by pneumatic or other fluid pressure, comprising a central supporting member, said member including a tubular part, a cylinder fixed to said member near its rear end, a reciprocating hammer piston slidably mounted between said central member and the cylinder and inclosed bythe latter, a cylindrical sleeve surrounding said cylinder and adapted to have limited longitudinal moveiient thereon, the sleeve having an internal annular recess near its forward end, cutters mounted within said sleeve and in the recess thereof for pivotal outward and forward movement, said central supporting member having at its forward end a stem engaging with the cutters to retain the same from displacement while perniitting movement thereof as specified, there being ports through the tubular portion of the central supporting member and piston whereby the introduc-b tion of fluid under pressure therethrough will cause the recipi'ocation of said piston, and means for cushioning the movement of the sleeve on the cylinder, thereby absorbing shocks on the cutters when struck by the hammer piston to minimize the breaking of the cutters by the repeated blows of the piston.

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5. A percussive tube scalingtool operated by pneumatic or other fluid pressure, comprising a central supporting member, a cylinder fixed to said member, a reciprocating hammer piston slidably mounted between said central member and the cylinder, a cylindrical sleeve surrounding said cylinder, cutters mounted at the fore end of said sleeve, said central supporting member having at its fore end a stem engaging within the cutters, means for introducing fluid under pressure through the centralsupporting member tov-thehammer piston, cylinder and sleeve, there being an annular recess between the cylinder and the sleeve connected with the fluid operating means, and cushioning springs disposed within said annular recess, substantially as set forth.

6. A percussive tube scaling tool operated by pneumatic or other fluid pressure, comprising a central supporting member of partially tubular formation, a hammer piston slidably mounted on said member, a cylinder Xed to said member, a sleeve surrounding and slidable on said cylinder, cutters pivotally mounted in said sleeve, a stem formed on the central member disposed within and engaging with said cutters, there being annular recesses within said piston, cylinder and sleeve, means for admitting fluid under pressure through the central member to the said recesses in the piston, cylinder and sleeve, substantially as set forth.

7 A percussive tube scaling tool operated by pneumatic or other fluid pressure, comprising a central supporting member of partially tubular formation, a reciprocating hammer piston slidably mounted on said member, a cylinder fixed to said hammer, a sleeve surrounding` and slidable on said cylinder, cutters pivotally mounted in said sleeve, a stem formed on the central member disposed within and engaging with said cutters, there being annular recesses within said piston, cylinder and sleeve, springs disposed within the annular recess between the said cylinder and sleeve, and means for admitting fluid under pressure through the central member to the annular recesses in the piston, cylinder and sleeve, substantially as set forth. l

8. A percussive tube scaling tool operated by pneumatic or other fluid pressure, compri sing a central supporting member, a cylinder fixed to said member, a reciprocating hammer piston slidably mounted between said central member and the cylinder, a cylindrical sleeve surrounding said cylinder, cutters mounted at the fore end of said sleeve, said central supporting member having at its fore end a stem engaging with the cutters and means for introducing fluid under pressure throughthe central supporting member to the hammer piston, cylinder and sleeve, there being an annular recess between` the cylinder and the sleeve connected with the fluid operating means.

9. l'n a percussive tube scaling tool operated by pneumatic. or other fluid pressure,

a sleeve, a series of cutters furnished at the fore end of the sleeve, said cutters having forward and outward motion, a rapidly reciprocating hammer piston controlling the motion of said cutter-sy a central `pressure admitting member, a cylinder fixed to said r member, said sleeve being slidably mounted on said cylinder, said cutters being positioned and maintained between the sleeve and thev central member without pivotal connection and means for returnin and 7 sleeve having forward and outward motion,

a stem on said central member adapted to engage within the cutters, said cutters being positioned and mounted between the sleeve and central member without pivotal connection, and Ameans for introducing fluid under pressure through the central supporting member to the hammer piston, cylinder and sleeve, substantially as set forth.

11.. A percussive tube scaling tool operated by pneumatic or other fluid pressure, comprising a central supporting fluid pressure admission member, a cylinder fixed to said member, a reciprocating hammer piston slidably mounted between said central member and the cylinder, a cushioned cylindrical sleeve surrounding said cylinder adapted to reciprocate, toothed scaling cutters mount` ed at the fore end` of said sleeve, the said central supporting member having at its fore end a stem positioned within and engaging with the cutters to maintain the cutters against said sleeve without pivotal connection, and means for introducing fluid under pressure through the central supporting member to the hammer piston, cylinder and sleeve, substantially as set forth.

l2. A percussive tube scaling tool operating by pneumatic or other fluid pressure, comprising a central supporting fluid pressure member, a cylinder fixed to said member, areciprocating hammer piston slidably mounted between said member and the cylinder, a cylindrical sleeve surrounding said cylinder adapted to reciprocate, cutters mounted at the fore end of said sleeve having forward and outward motion, said cen- V tral supporting member having at its fore end a stem positioned within and engaging with the cutters to maintain the cutters against said sleeve without pivotal connec tion, meansy for introducing fluid under pressure ,i througlithe central supporting rmember,tothe hammer piston, cylinder and sleeve, andv cushioning springs disposed between the cylinder and the sleeve, substantially as set forth.

13.' A. percussive tube scaling tool operated .byvpneumatic or other fluid pressure, comprising acentral fluid pressure admission supporting member of partially tubular formation, a hammer piston-mounted on said member adapted to rapidly reciprocate under fluid pressure, a cylinder fixed to said member within which the reciprocating piston isdisposed, a combined sleeve surrounding and sl-idable on said cylinder, toothed cutters havingvforward andoutward motion mounted in the fore end of said sleeve, a stem formed on the central member disposed yWithin and engaging withsaid cutters to maintainf the cutters against `said sleeve without pivotal connection, meansfor admitting fluid under pressure through the copies of this patenty may be qbtined for cential member to the said piston cylinder and sleeve, substantially as set forth.

14. A percussive tube scaling tool operated by pneumatic or other fluid pressure, comprising a central supporting fluid pressure admission member of partially tubular formation, a reciprocating hammer piston slidably mounted on said member, a cylinpressure through the central member to the piston, cylinder and sleeve, substantially as set forth.

ln testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

HARRY SAMUEL BICKERTON BRINDLEY. lllitnesses:

J our Hiiaeiiovii, MAMAN ELIZABETH STAFFORD Grimani.

ive cents each, by addressing the Commissioner of .Patents` Washington, D. C.

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